Concrete volume calculator (slab, floor, foundation)

Calculate how many cubic meters of concrete you need for a slab, floor or foundation.

Concrete needed

2.1 m³

Volume without waste2 m³

In liters2,100 L

For ready-mix, round up when ordering (delivered per m³). For bagged concrete, check the yield on the package.

How the calculation works

The volume is length × width × thickness, with thickness in meters (cm ÷ 100). Add a waste margin (≈5%) for spillage and variation.

How many cement bags per m³?

It depends on the mix, but common concrete uses about 7 bags of 50 kg per m³.

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Updated on June 18, 2026 · by Rafael Rossi · Methodology & sources